Global NEST Journal

ISSN:

Print ISSN: 1790-7632

Electronic ISSN: 2241-777X

Issue 2

Volume number:

16

Publication year:

2014

Publication month:

May

Articles

A handy irrigation management method through meteorological data. Case study in N. Greece

Arampatzis G., Hatzigiannakis E. , Evangelides C. and Panagopoulos A., Pages:219-228

DOI:

https://doi.org/10.30955/gnj.001283

Paper Topic:

Water Resources Management

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Abstract

Crop irrigation, especially in irrigation networks, often consumes larger quantities of irrigation water than necessary since most of the times irrigation is carried out empirically and not based on actual crop requirements. The aim of this work is the management of irrigation water though the use of meteorological data. This approach was utilized for the first time in Greece and applied in a pilot area of about 6,000 ha at the Local Organization of Land Reclamation in Nigrita. The method is based on accurate calculation of daily evapotranspiration of the common cultivations at the area (maize, cotton, alfalfa), using meteorological data. Thus irrigation is organized based on actual water consumption of the crops ensuring the qualitative and quantitative characteristics of their products.

Soil mapping to assess workability in central Italy as climate change adaptation technique

Servadio P., Bergonzoli S. and Toderi M. , Pages:229-239

DOI:

https://doi.org/10.30955/gnj.001299

Paper Topic:

Ecosystems and Natural Resources Management

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Abstract

In this paper soil conventional tillage (CT) in two adiacent on-farm sites, hilly and plain fields, was carried out in comparison with direct-seeding + fertilizing at very low water content. The quality and quantity of work were evaluated through machine performance, fossil-fuel energy requirements and carbon dioxide emissions from agricultural machinery. The fields were previously sampled and mapped to investigate spatial variability of soil properties, to find soil quality indicators and to asses soil workability. The results revealed good traction performance during CT operations (slip values were lower than 15%). During plowing, time efficiency of the wheeled tractor was 40% lower with respect to the tracked tractor. Global energy employed was of the same magnitude for the tracked and wheeled tractor (220 kWh ha^-1) while was significantly lower (52 kWh ha^-1) for direct-seeding+fertilizing. The degree of crushing of the soil caused by CT required further energy employed (98 kWh ha^-1) to seedbed preparation. Fossil-fuel energy requirements from agricultural machinery were significantly lower during direct-seeding+fertilizing (0.52 GJ ha^-1) with respect to the conventional soil tillage (2.30 GJ ha^-1). Wheat yield of direct seeded field and the total cost of the crop cycle (€/ha) were 9% and 16% lower respectively than the values recorded on fields under conventional tillage.

Essential oil composition and antimicrobial investigation of some Iranian herbal plants on Pectobacterium carotovorum

Mehrsorosh H., Gavanji S., Larki B., Mohammadi M.D., Karbasiun A., Bakhtari A., Hashemzadeh F. and Mojiri A. , Pages:240-251

DOI:

https://doi.org/10.30955/gnj.001205

Paper Topic:

General

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Abstract

In recent years, there has been growing concern regarding undesirable side effects of synthetic antimicrobial drugs used for food preservation or in medicine and an explosive global spreading of multidrug resistant microbes are considered as a substantial global health threat. This necessitates the searching for new classes of safe and more effective antimicrobial agent by acting with different mechanisms. This study aimed to determine the antimicrobial activity of essential oils of some herbs which are endemic Iranian plants using minimum inhibitory (MIC) concentration of their essential oils. Results obtained from minimum inhibitory concentration showed that the essential oil of Thymus vulgaris, compared to other extracts, possess the best inhibitory effect in the lowest concentration. The extracts of Artemisia kermanensis, Lavandula officinalis, Rosemarinous officinalis and Eucalyptus caesia are reported to have inhibitory effect on Pectobacterium carotovorum.

Lower Douro River basin (Portugal) water quality – Focus on trace element changes and anthropogenic sources of contamination

Couto C., Pinto I., Vieira Madureira T., Rocha M.J., Tiritan M.E., Lopes J.A. and Almeida A., Pages:252-268

DOI:

https://doi.org/10.30955/gnj.001341

Paper Topic:

Water Quality

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Abstract

The Douro River lower basin water quality was studied regarding its concentration on 18 trace elements (Be, Al, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sb, Ba, Tl, Pb and U, measured by ICP-MS). Other physicochemical parameters, such as pH, conductivity, dissolved oxygen and water temperature were also determined in situ.

To take into account the expected spatio-temporal changes and to look for anthropogenic influences on trace element levels, samples (n=88) were collected at 11 sampling sites in four sampling campaigns (October 2007; January, March and July 2008), in both low and high tides, in order to evaluate spatial, seasonal and tidal changes.

A multivariate approach – principal component analysis – was used to investigate interelement correlations and the variability observed in the different data sets.

According to aquatic life limits (CCME, 2011), the quality of Douro River water was found acceptable. Except for DO, where a significant number of samples presented levels below 5.0 mg l^-1, Cr(VI) (mean±sd = 3.09±1.54; median = 2.82 ppb) and Se (10.9±10.1; 7.74 ppb) all the other parameters measured fell well within acceptable limits. Occasional high levels were found for most trace elements, reflecting sporadic and local inputs. Important spatial differences in trace element levels were also found. Except for Be, Al and Mn, most metals tended to increase in the downstream direction. Some trace elements related with agriculture practices (Zn, Cu and Ni) were higher in samples collected on sampling sites located at the middle part of the studied area and were highly correlated, reflecting an eventual common source. Important seasonal differences in trace element levels were also observed, e.g., October samples were generally characterized by higher Ni, Cu, Zn and Pb levels.

Gas monitoring methodology and application to CCS projects as defined by atmospheric and remote sensing survey in the natural analogue of Campo de Calatrava

Ortega M.F. , Rincones M. , Elío J. , Gutiérrez del Olmo J., Nisi B., Mazadiego L.F., Iglesias L., Vaselli O., Grandia F., García R., De La Vega R. and Llamas B. , Pages:269-279

DOI:

https://doi.org/10.30955/gnj.001242

Paper Topic:

General

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Abstract

CO₂capture and storage (CCS) projects are presently developed to reduce the emission of anthropogenic CO₂ into the atmosphere. CCS technologies are expected to account for the 20% of the CO₂ reduction by 2050. Geophysical, ground deformation and geochemical monitoring have been carried out to detect potential leakage, and, in the event that this occurs, identify and quantify it. This monitoring needs to be developed prior, during and after the injection stage. For a correct interpretation and quantification of the leakage, it is essential to establish a pre-injection characterization (baseline) of the area affected by the CO₂ storage at reservoir level as well as at shallow depth, surface and atmosphere, via soil gas measurements. Therefore, the methodological approach is important because it can affect the spatial and temporal variability of this flux and even jeopardize the total value of CO₂ in a given area.

In this sense, measurements of CO₂ flux were done using portable infrared analyzers (i.e., accumulation chambers) adapted to monitoring the geological storage of CO₂, and other measurements of trace gases, e.g. radon isotopes and remote sensing imagery were tested in the natural analogue of Campo de Calatrava (Ciudad Real, Spain) with the aim to apply in CO₂ leakage detection; thus, observing a high correlation between CO₂ and radon (r=0,858) and detecting some vegetation indices that may be successfully applied for the leakage detection.

Time Series Modelling of Pan Evaporation-A Case Study in the Northeast India

Dabral P.P., Jhajharia D., Mishra P., Hangshing L. and Doley B.J., Pages:280-292

DOI:

https://doi.org/10.30955/gnj.001317

Paper Topic:

Hydrology and water resources

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Abstract

In the present study, a monthly time series model was developed for pan evaporation (E_pan) in Jorhat (Assam), northeast India. We assume that the E_pan series can be decomposed into deterministic and stochastic components, and a turning point test was used to identify the presence of a trend component in the series. A trend-free E_pan time series was further obtained by eliminating the trend component from the original E_pan time series, and later used in identifying the periodic component using Fourier series analysis. Results show that the first three harmonics explained the total variance by 88,2 %. Before modelling the stochastic dependent component, the periodic component was removed from the time series. In the stochastic dependent component modelling, the moving average (MA) model of order 2 was found suitable on the basis of minimum value of the Bayesian information criterion (BIC). The independent stochastic component was modelled using the normal distribution function. Overall, a very good agreement is observed between generated and historical records, with the Nash-Sutcliffe coefficient being equal to 0,98.

Spatialised agricultural nitrogen balance of Veneto region, Northern Italy: sources identification, assessment and policy relevance

Pulighe G., Vanino S., Lupia F. and Altobelli F., Pages:293-305

DOI:

https://doi.org/10.30955/gnj.001213

Paper Topic:

Ecosystems and Natural Resources Management

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Abstract

The aim of this study is to deepening knowledge on the agricultural nitrogen cycle within the Veneto region (Northern Italy) by computing the Gross Nitrogen Balance (GNB) with highly geographical resolution. Spatialised maps of nitrogen input and output, created using the most detailed information available, are important tools for assessing environmental sustainability.

Nitrogen mass balances, computed at regional level for 2007, suggest a large N surplus in this area, over 82,485 t N year⁻¹. Calculations indicate a large impact of animal husbandry and agricultural activities in this region, with livestock manure and synthetic fertilizers contributing 87.7 % of total N inputs (about 208,050 t N year⁻¹), largely exceeding N outputs (about 1,255,644 t N year⁻¹). The GIS-based analysis highlights interdependencies between farmer’s choices of land uses and the environmental pressures of agricultural activities at the sub-regional level. The results of the study can be used to inform policy makers about the effects caused by environmental management actions, that should take into account the interlinkages between landscapes, habitats, biodiversity and ecological integrity.

Effects of climate change on future extreme rainfall indices over Thailand

Maijandee S., Kreasuwun J. , Komonjinda S. and Promnopas W., Pages:306-315

DOI:

https://doi.org/10.30955/gnj.001227

Paper Topic:

Global Environmental Change

Issue:

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Abstract

Extreme rainfall indices were calculated based on daily rainfall data derived from the outputs of MM5-RCM simulations. Projected changes of these indices in the future (2020s) under the IPCC Special Report on Emissions Scenarios (SRES) A1B compared to the reference period (1990s) were analyzed. Before calculating the indices, the raw outputs from the MM5-RCM were adjusted in order to reduce biases as part of the bias-correction process. The validation demonstrates that the average and cycle of annual rainfall in the reference period are reproduced reasonably in the bias-corrected MM5-RCM results. The projected changes of the rainfall indices suggest that in the future most areas of northern, western, and northeastern Thailand will become wetter in the wet season and drier in the dry season. Central and eastern Thailand will become drier in the wet season while in the dry season rainfall will become more intense, and rainy days will become more scattered with a higher number of heavy rainfall days. In the south, the length of the wet spell will be decreased in the Southern Andaman Sea area and increased in East-Southern Region. The dry spell will likely be shorter throughout the southern region for all seasons.

Environmental Dynamics and Engineered Systems for the Degradation of Trichloroethylene: A Critical Review

Amin M.T., Hamid S., Alazba A.A., Amin M.N., Islam M. and Manzoor U. , Pages:316-328

DOI:

https://doi.org/10.30955/gnj.001333

Paper Topic:

General

Issue:

Issue 2

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Abstract

Trichloroethylene (TCE) is found in all mediums of environment in varying concentrations. Over the past 25 years, many engineered systems have been devised for its complete and sustainable degradation. This study reviews the environmental factors that influence the TCE pollution in environment and its biological mineralization via engineered systems. Although at some polluted sites natural attenuation of TCE has been found to occur but generally the natural process is very slow. The use of nanoparticles and composites provides a comparatively novel approach for the treatment of TCE contaminated waters. Biological engineered systems have been found to degrade TCE on much faster rates and higher concentrations. To identify the appropriate microorganisms in any engineered system that can effectively provide a low-cost treatment option for TCE degradation is the pressing need at the moment. Adding a second distinct organic phase to the aqueous medium for degrading fast and high concentration of TCE is recommended. The organic phase, which do not mix with the aqueous phase and can be easily separated, discharged, and reuse, should be selected based on its insolubility, volatility, non-biodegradability by the selected microorganism and the cost of the overall engineered system. Biodegradation offers the potential of cost effective treatment of TCE, however, that engineered systems should effectively use the biodegradative metabolism that nature has evolved.

Influence of coal properties on the co-combustion characteristics of low-grade coal and city mud

Yan Y.F., Zhang Z.E., Zhang L. and Zhang L., Pages:329-338

DOI:

https://doi.org/10.30955/gnj.001315

Paper Topic:

General

Issue:

Issue 2

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Abstract

In this paper, the effects of the mixing ratio and particle size of coal were investigated using a thermogravimetric analysis (TGA). A method of Achar-Brindley-Sharp-Wendworth (ABSW) was applied to a simultaneous calculation of the kinetic parameters (including the apparent activation energy, the reaction order and the frequency factor). Meanwhile, this study also revealed that both the burning performance and the characteristic parameters improved when sludge mixing ratio was smaller (10 wt.%). The ignition temperature advanced with an increase of the sludge proportion, while the combustion characteristic index dropped. As the sludge mixture ratio rose to 70 wt.%, the DTG curve reached three peaks at 293 °C, 580 °C and 748 °C Decreasing the coal particle size led to the advancement of the devolatilization, fixed carbon burning stage and maximum weight loss rate, and the reduction of the corresponding temperature. Additionally, the apparent activation energy and frequency factor of the mixture reduced when the proportion of the sludge mixing ratio went up. Also, the experiment results indicated that with the decline of the particle size distribution of coal, the apparent activation energy followed a downward trend, while the frequency factor increased.

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